> Ah, something that tracks you based on appearance, and can later do so outside stores, is very different from a keychain fob that you can register with 555-867-5309.

That's a fair argument, but I think Amazon has enough about me that what you're suggesting is a minor concern relative to what they already have.

I'm much more concerned about my Amazon search history getting leaked as a .txt file than I am about Amazon using imagery of me to train their ML models.